The acoustic tour is almost an inevitability. Serving as a retrospective (see: Alanis Morrissette’s Jagged Little Pill Acoustic tour and Peter Frampton’s Acoustic Classics tour), artists will take it on after a one-off performance garners rave reviews (see: crowd demand to see an old favorite, or T-Pain post-Tiny Desk Concert). But still, the question begs, “Why go on an acoustic tour after only two albums?” Lucius’s live show has always featured an acoustic element, but only for one song before going back to their usual setup. Their debut album Wildewoman also toyed with Americana-tinged singer-songwriter music, like “Two of Us on the Run.” But after two albums, vocalists Jess Wolfe and Holly Laessig have decided to take that fan favorite moment of their show and expand on it. Their third album Nudes features acoustic versions of select Lucius tracks from previous albums as well as a few covers, including a collaboration with Pink Floyd’s Roger Waters. It’s Lucius as fans have only received a sample of up to now, but at their sold-out Lincoln Theatre stop, they performed a fully-acoustic set that was nothing short of captivating from start to finish.